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211.
The objectives of the study are to present a critical review of the 238U, 234U, 235U, 226Ra and 210Pb levels in water samples from the EPA studies (U.S. EPA in Abandoned uranium mines and the Navajo Nation: Red Valley chapter screening assessment report. Region 9 Superfund Program, San Francisco, 2004, Abandoned uranium mines and the Navajo Nation: Northern aum region screening assessment report. Region 9 Superfund Program, San Francisco, 2006, Health and environmental impacts of uranium contamination, 5-year plan. Region 9 Superfund Program, San Franciso, 2008) and the dose assessment for the population due to ingestion of water containing 238U and 234U. The water quality data were taken from Sect. “Data analysis” of the published report, titled Abandoned Uranium Mines Project Arizona, New Mexico, Utah–Navajo Lands 1994–2000, Project Atlas. Total uranium concentration was above the maximum concentration level for drinking water (7.410–1 Bq/L) in 19 % of the water samples, while 238U and 234U concentrations were above in 14 and 17 % of the water samples, respectively. 226Ra and 210Pb concentrations in water samples were in the range of 3.7 × 10?1 to 5.55 × 102 Bq/L and 1.11 to 4.33 × 102 Bq/L, respectively. For only two samples, the 226Ra concentrations exceeded the MCL for total Ra for drinking water (0.185 Bq/L). However, the 210Pb/226Ra ratios varied from 0.11 to 47.00, and ratios above 1.00 were observed in 71 % of the samples. Secular equilibrium of the natural uranium series was not observed in the data record for most of the water samples. Moreover, the 235U/totalU mass ratios ranged from 0.06 to 5.9 %, and the natural mass ratio of 235U to totalU (0.72 %) was observed in only 16 % of the water samples, ratios above or below the natural ratio could not be explained based on data reported by U.S. EPA. In addition, statistical evaluations showed no correlations among the distribution of the radionuclide concentrations in the majority of the water samples, indicating more than one source of contamination could contribute to the sampled sources. The effective doses due to ingestion of the minimum uranium concentrations in water samples exceed the average dose considering inhalation and ingestion of regular diet for other populations around the world (1 μSv/year). The maximum doses due to ingestion of 238U or 234U were above the international limit for effective dose for members of the public (1 mSv/year), except for inhabitants of two chapters. The highest effective dose was estimated for inhabitants of Cove, and it was almost 20 times the international limit for members of the public. These results indicate that ingestion of water from some of the sampled sources poses health risks.  相似文献   
212.
Calls for biodiversity conservation practice to be more evidence based are growing, and we agree evidence use in conservation practice needs improvement. However, evidence-based conservation will not be realized without improved access to evidence. In medicine, unlike in conservation, a well-established and well-funded layer of intermediary individuals and organizations engage with medical practitioners, synthesize primary research relevant to decision making, and make evidence easily accessible. These intermediaries prepare targeted evidence summaries and distribute them to practitioners faced with time-sensitive and value-laden decisions. To be effective, these intermediaries, who we refer to as evidence bridges, should identify research topics based on the priorities of practitioners; synthesize evidence; prepare and distribute easy-to-find and easy-to-use evidence summaries; and develop and maintain networks of connections with researchers and practitioners. Based on a review of the literature regarding evidence intermediaries in conservation and environmental management, as well as an anonymous questionnaire searching for such organizations, we found few intermediaries that met all these criteria. Few evidence bridges that do exist are unable to reach most conservation practitioners, which include resource managers in government and industry, conservation organizations, and farmers and other private landowners. We argue that the lack of evidence bridges from research to practitioners contributes to evidence complacency and limits the use of evidence in conservation action. Nevertheless, several existing organizations help reduce the gap between evidence and practice and could serve as a foundation for building additional components of evidence bridges in conservation. Although evidence bridges need expertise in research and evidence synthesis, they also require expertise in identifying and communicating with the community of practitioners most in need of clear and concise syntheses of evidence. Article Impact Statement: Evidence-based conservation will not be realized without improved access to evidence. We call for intermediary evidence bridges.  相似文献   
213.
Environmental Fluid Mechanics - Following the 2010 Mentawai tsunami, observations in Sumatra by Hill et al. (J Geophys Res Solid Earth, 2012. https://doi.org/10.1029/2012jb009159 ) noted enhanced...  相似文献   
214.
Helen Young  Musa Adam Ismail 《Disasters》2019,43(Z3):S318-S344
Darfur farming and pastoralist livelihoods are both adaptations to the environmental variability that characterises the region. This article describes this adaptation and the longer‐term transformation of these specialised livelihoods from the perspective of local communities. Over several decades farmers and herders have experienced a continuous stream of climate, conflict and other shocks, which, combined with wider processes of change, have transformed livelihoods and undermined livelihood institutions. Their well‐rehearsed specialist strategies are now combined with new strategies to cope. These responses help people get by in the short term but risk antagonising not only their specialist strategies but also those of others. A combination of factors has undermined the former integration between farming and pastoralism and their livelihood institutions. Efforts to build resilience in similar contexts must take a long‐term view of livelihood adaptation as a specialisation, and consider the implications of new strategies for the continuity and integration of livelihood specialisations.  相似文献   
215.
This paper develops a simple model and suggests a plausible chemico-physical mechanism for a non-linear response between atmospheric sulphur and sulphur emissions. It contains simplified representations of transport, deposition and conversion processes and uses a proxy in-cloud oxidant-limited reaction along a pathway connecting an emission source with a receptor site. Individual pathway responses to emissions show linear behaviour above a threshold. However, by averaging the values of SO2 at the receptor site from different pathways a continuous non-linear relationship is obtained. As emissions reduce, distant emission sources become less significant contributors of sulphur dioxide at a receptor site but their emissions are still counted in an emission inventory, leading to an apparent non-linearity. Sulphate is always found to contribute a signal to the receptor site total. This model goes someway to explaining a proposed 'crossover' between observed proportions of wet and dry deposited sulphur in the UK as emissions have been reduced.  相似文献   
216.
The long term behaviour of CFBC ash-water systems   总被引:2,自引:0,他引:2  
Circulating fluidized bed combustion (CFBC) ashes in contact with water, whether in liquid or vapour form, exhibit considerable chemical activity, which can continue for more than a year. From the point of view of the setting of CFBC ash-water mixtures and their behaviour, the formation of gypsum and of ettringite are important. The crystallisation of ettringite is associated with expansion of the set mass and absorption of water into the solids, but the ash-water system as a whole shrinks. The extent of ettringite formation is reduced if carbonation of free lime can take place. There is little carbonation if the set solids are covered by water but if contact with air is not restricted, the ettringite formed earlier slowly decomposes, its place being taken by calcite and gypsum. The fate of the aluminium from decomposed ettringite is uncertain; no new crystalline Al compounds are found. It appears that ultimately most analytical lime present can become carbonated. This is environmentally beneficial since it reduces chemical activity in the landfill, and reduces the amount of CO2 released due to limestone use. The main features of the behaviour of CFBC ash-water mixtures can be reproduced in model systems (CaO-Al2O3-CaSO4-H2O) but that of real ashes is complicated by the presence of silicates and possible interactions between silica and the strongly alkaline aqueous medium. Also, aluminates present in the ash are probably more active with respect to ettringite formation than pure aluminum hydroxide.  相似文献   
217.
Capacity building is widely recognised as a central feature of Integrated Coastal Zone Management (ICZM). Yet, although increased community capacity can potentially empower local communities with the ability to tackle the impacts of socio-economic change, an evaluation of ICZM performance reveals a limited interest in advancing community development initiatives. This weakness is particularly apparent in Scotland. Whilst coastal communities in Scotland have been found to suffer from a range of significant socio-economic problems, Scottish approaches to ICZM have failed to improve local development trajectories. In response, this paper considers the degree to which community based partnerships can assist in the delivery of sustainable development benefits.  相似文献   
218.
This study investigated how the occurrence and magnitude of first flush events in stormwater may influence the effective management of urban runoff pollution. To facilitate the understanding of the first flush phenomenon on a seasonal scale, the City of San Jose, CA carried out an investigation between May 1997 and April 2000 to characterize concentrations of pollutants in local waterbodies during eight storm events. The purpose of the investigation was twofold: (1) To determine if concentrations of specific constituents in stormwater runoff are elevated during the first substantial storm of the wet season, and (2) To identify the physical and environmental conditions surrounding such events. Concentration data for total and dissolved metals, pesticides, polyaromatic hydrocarbons, anions, total suspended solids, total organic carbon, conductivity, gasoline and diesel, and volatile and semi-volatile organics were collected at over 25 sites. Monitoring data analysis focused on identifying physical and environmental conditions yielding increased levels of pollutants during the first substantial storms of the rainy season compared to other storm events. Quantitative analysis focused on metals and anions because most observations for other constituents were below detectable levels. The results suggest that first flush phenomena did not occur consistently throughout most of the stations investigated. The results further suggest that there are specific combinations of site and storm conditions that result in a first flush effect with respect to dissolved metals. Based on the results of this and related investigations, implications for urban runoff management are discussed. For example, if dissolved metals are of principal concern, it may be worthwhile to optimize existing control strategies to minimize pollutant loading from storms that are preceded by an extended dry period.  相似文献   
219.
This research develops a method to transform the Oregon Benchmarks, a set of internationally recognized quantitative indicators designed to measure a broad array of state-level trends, into indices of social, economic, and environmental sustainability. Through multiple means, an original set of 90 Oregon Benchmarks has been narrowed into a smaller set of sustainability indicators in order to gain an integrated view of statewide sustainability as well as the capacity to look at social, environmental, and economic sustainability in isolation. The three-domain sustainability indices presented here are designed both to understand the current sustainability situation and to create a useful and informative tool for state-level policy makers interested in incorporating sustainability principles into their decision making.  相似文献   
220.
The business excellence through resource efficiency (betre) project aimed to increase awareness of the benefits of waste minimisation for SMEs in West Sussex, South East England. The programme was run by the West Sussex Sustainable Business Partnership, a collaboration of all West Sussex Local Authorities, the Environment Agency and EcoSys (a service provider). Betre provided a range of free business support and advice over an 18-month period including; workshops, newsletters, audits, grants and a technical Helpline. Information on environmental compliance and Best Practice for waste minimisation, recycling, energy and water efficiency was disseminated. All activities were linked with the UK government's Best Practice programmes. Although company recruitment was initially slow, betre was ultimately extremely successful at attracting companies to join; with 308 recruited. This is probably the most successful recruitment to a project, of this type, in the UK to date. Over half of the business members became actively involved and attended training events or had environmental audits. There were over 200 improvement actions identified by 64 of the participating companies. These resulted in estimated cost savings of at least £215 000 per annum. In addition, actions taken to prevent pollution and ensure compliance with environmental legislation have the potential to save businesses a further £204 000 in possible penalties. The environmental impact of the project has been significant, with reductions identified in waste (1437 tonnes), water (62 933 m3) and energy (15 million kW h—equivalent to 668 tonnes CO2). In addition to actions with directly measurable results, betre has stimulated long-term benefits by addressing pollution prevention and compliance, through the formulation of environmental policies and from the adoption of Environmental Management Systems. One of the key learning points is that it may have been better to devote less time to running training events and instead to have diverted this time to increased business support, mainly through audits. To capitalise on this success, a new project is being planned to disseminate Best Practice.  相似文献   
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